Yes, I was surprised to find out the cost, too. One place was only $35/day ($500 deposit), but the other was going with $75/day, until I told them that the car rental would only be $40/day. But the latter was prepared to drop off and pick up at my hotel, which I pretty much needed due to timing.
I starting a similar thread to this in Commuting, about how I found out shortly after posting this that I would not be able to take it as a business expense, which probably kills it for me. Seems my company excludes motorcycles as a legitimate mode of business transportation, and the person communicating this said that probably bicycles would be viewed the same way. Someone else then suggested a folder, which I think is a great idea. But probably not in time.